蛋白质纳米纤维及其与金属离子的水凝胶形成,ACS Nano

当前位置： X-MOL 学术 › ACS Nano › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

蛋白质纳米纤维及其与金属离子的水凝胶形成
ACS Nano ( IF 17.1 ) Pub Date : 2021-03-05 , DOI: 10.1021/acsnano.0c10893
Xinchen Ye ₁ , Antonio J. Capezza ₁ , Xiong Xiao ₁ , Christofer Lendel ₂ , Mikael S. Hedenqvist ₁ , Vadim G. Kessler ₃ , Richard T. Olsson ₁

Affiliation

已通过在低pH和不同金属离子存在下通过乳清蛋白原纤化制备蛋白纳米原纤（PNF）。从PNF悬浮胶凝行为和原纤化动力学方面系统地研究了金属离子的作用。金属离子的高价态和小的离子半径（例如Sn ⁴⁺）导致已经在30 mM的金属离子浓度下形成水凝胶，而中等价态和较大的离子半径（Co ²⁺（Ni 2 ⁺，Al ³⁺）导致水凝胶形成发生在60 mM处。浓度为120 mM的Na ⁺需要使用PFA来形成PNF水凝胶，而较低的浓度则显示出与未引入金属离子的参比PNF溶液相似的液体行为。水凝胶力学在稳态条件下温育/凝胶化的24小时后进行了研究，揭示了更多的酸性（更小和更带电）的金属离子诱导CA。对于相同浓度的金属离子，与酸性较低的金属离子（电荷较小，半径较大）相比，储能模量高2个数量级。水凝胶的粘弹性本质归因于金属离子协调PNF附近的水分子的能力。在PNF的生长过程中，溶液中金属离子的存在通常会导致弯曲的原纤维，而当形成氧化物/氢氧化物时，浓度上限存在上限，并且水凝胶会由于相分离而失去其凝胶性质。硫黄素T（ThT）荧光用于确定原纤维形成率，占总PNF的50％（t _1/2），从2.3降至约。0.5小时，具体取决于所添加的特定金属离子。

"点击查看英文标题和摘要"

Protein Nanofibrils and Their Hydrogel Formation with Metal Ions

Protein nanofibrils (PNFs) have been prepared by whey protein fibrillation at low pH and in the presence of different metal ions. The effect of the metal ions was systematically studied both in terms of PNF suspension gelation behavior and fibrillation kinetics. A high valence state and a small ionic radius (e.g., Sn⁴⁺) of the metal ion resulted in the formation of hydrogels already at a metal ion concentration of 30 mM, whereas an intermediate valence state and larger ionic radius (Co²⁺, Ni²⁺, Al³⁺) resulted in the hydrogel formation occurring at 60 mM. A concentration of 120 mM of Na⁺ was needed to form a PNF hydrogel, while lower concentrations showed liquid behaviors similar to the reference PNF solution where no metal ions had been introduced. The hydrogel mechanics were investigated at steady-state conditions after 24 h of incubation/gelation, revealing that more acidic (smaller and more charged) metal ions induced ca. 2 orders of magnitude higher storage modulus as compared to the less acidic metal ions (with smaller charge and larger radius) for the same concentration of metal ions. The viscoelastic nature of the hydrogels was attributed to the ability of the metal ions to coordinate water molecules in the vicinity of the PNFs. The presence of metal ions in the solutions during the growth of the PNFs typically resulted in curved fibrils, whereas an upper limit of the concentration existed when oxides/hydroxides were formed, and the hydrogels lost their gel properties due to phase separation. Thioflavin T (ThT) fluorescence was used to determine the rate of the fibrillation to form 50% of the total PNFs (t_1/2), which decreased from 2.3 to ca. 0.5 h depending on the specific metal ions added.

更新日期：2021-03-23

点击分享查看原文

点击收藏

公开下载

阅读更多本刊最新论文本刊介绍/投稿指南

全部期刊列表>>